Oil/Water exchange heater

[Danny DeVito]

Does anyone know how this works .? It is bolted to the side of the filter housing to supposedly transfer heat from the oil to the water. But i don;t see why it only has one pipe which goes into the front of the block. Does it heat the water and the water just forces itself into the block >?? Anybody know ?

 

[jaymanek]

its an oil cooler... so the oil runs through it and water cooling system cools it. Recipe for disaster IMO!

 

[LastMinute]

I think Danny's question is how does the water cooling work, given that there's only one water pipe and thus no obvious way for the water to flow through the cooler?

 

[jaymanek]

there are two pipes as far as i remember

 

[LastMinute]

No expert, but there's only one pipe illustrated here.

I wonder if the water goes out through the pipe and in from the timing case, through the back face of the cooler (where the oil enters and exits)?

 

[kth286]

its an oil cooler... so the oil runs through it and water cooling system cools it. Recipe for disaster IMO!

That is why I always say use the proper Merc coolant with non hard water.

This aspect of car maintenance is not given enough importance by a long shot, with the subsequent corrosion causing all sorts of problems far before it needs to.

My original Rad still on car at 175,000 miles and 15 years.

 

[Danny DeVito]

Well mine is 638 but none of the pics show an exit hole The face visible in the 202 is the face that bolts to the filter housing but no holes are visible. I can find no water flow diagram in wis either.

 

[Danny DeVito]

Another question while its there. In the first pic is the stat housing. Above the big pipe is the expansion bottle top hose connection. Would this pipe be rad side or block side of the stat ? I think its rad side but cannot remember.

 

[Tiff]

You'll probably find its the block side- these are heat exchangers. They heat the oil more quickly as the coolant warms up to temp, then cools the oil as it goes up past the temp of the coolant- that's how it used to work on VW / Audi anyway.

 

[jaymanek]

That is why I always say use the proper Merc coolant with non hard water.

This aspect of car maintenance is not given enough importance by a long shot, with the subsequent corrosion causing all sorts of problems far before it needs to.

My original Rad still on car at 175,000 miles and 15 years.

We did have one of these fail on a 2007 C180, only 20K on the clock..It was just out of warranty!...
unfortunately we assumed it was the head gasket and replaced the gasket along with all the other normal bits... Spent hundreds... then we scratched our heads wondering what we had done wrong as there was still coolant in the oil... and lots of it...
Then we noticed the heat exchanger and we put a new one on.. no more mixing.
I think we had to flush the engine over 10 times on that car!

 

[Tiff]

We did have one of these fail on a 2007 C180, only 20K on the clock..It was just out of warranty!...
unfortunately we assumed it was the head gasket and replaced the gasket along with all the other normal bits... Spent hundreds... then we scratched our heads wondering what we had done wrong as there was still coolant in the oil... and lots of it...
Then we noticed the heat exchanger and we put a new one on.. no more mixing.
I think we had to flush the engine over 10 times on that car!

Ditto, but with a VW Passat...

 

[Danny DeVito]

I wonder how efficient it is ? Seems a bit fiddly